Startups are risky. Adding more risk on top of that without specific expected gains in an area that doesn’t incur much ongoing cost is a bad business decision.
I will state this plainly. It’s laziness. He knows how to use Jira and doesn’t want to spend time learning a new tool. There is no risk involved with these anymore. It’s not a risk, it’s effort.
Using Jira is a form of organizational debt. He didn’t want to put in the work up front to set up something better because he knew Jira already, which is fine. But everyone on the engineering team pays the price every day now because Jira is awful. You have to decide, is it worth spending 10 hours on the weekend learning Linear or do I make my whole organization suffer? He chose the former. But it’s not a risk mitigation thing. It’s a time trade-off thing.